Repeater mill arrangement



June 19, 1962 L. C. PIETSCH REPEATER MILL ARRANGEMENT Filed March 3, 1959 INVENTOR.

United States atent ()fiice 3,039,335 Patented June 19, 1962 3,039,335 REPEATER MILL ARRANGEMENT Leonard C. Pietsch, Joliet, Ill., assignor to Union Tank Car Company, Chicago, Ill., a corporation of New Jersey Filed Mar. 3, 1959, Ser. No. 796,872 2 Claims. (Cl. 8052) The invention relates to a repeater mill, and more particularly to an arrangement thereof designed to accommodate smooth billet flow.

Those skilled in the art of steel manufacture, and particularly the manufacture of steel bars of varying cross section such as reinforcing bars and the like, are familiar with the type of mill known as a repeater mill. The mill per se comprises a plurality of forming dies in operative series relationship to each other, designed to progressively reduce and reform the cross sectional area of a feeding billet. In addition, each die arrangement is provided with roller means and the like, which accomplish the progressive feeding of the billet through the series-arranged dies. One of the most desirable forms of a repeater mill is to place the dies in side-by side relationship with their working axes substantially parallel. To provide operative communication between the dies, the series of arcuate U-shaped channels interconnect the output side of one die and the input or feed side of the next die in the series relationship. In the operation of such a mill, a billetheating oven is provided to raise the billet temperature to a proper level to accommodate plastic forming of the billet. After heating, the billets are conveyed to the first die and fed therethrough. Under the squeezing and forming action of the die, the billet is reduced in cross sectional area, formed to a desired contour, and of course as a result thereof is elongated axially. Upon feeding from the output side of the first die, the now-elongated and reformed billet is conveyed into a channel which guides the leading edge of the billet through the next forming die. The second forming die accomplishes the same function in that the reformed billet is further reformed, reduced in cross sectional area and fed into a second channel which carries the leading edge of the billet to a third stage. The progress of each billet through each die is sometimes referred to as a pass. It will be apparent that the number of stages or passes required in a given mill operation will vary depending upon the final bar shape, the original billet size and the amount of area reduction required.

In order to conserve factory space, it is desirable to position the sequential repeater mill stages in as small as possible factory floor space area. For this reason, repeater mills employing the arcuate or U-shaped feeding channels mentioned above are particularly desirable. It will be apparent, however, that as the billet is fed from a first to a second stage, various portions thereof will be simultaneously operated on in the first and second stages. That is, the leading edge of the moving or feeding billet will enter the second stage for reforming and cross sectional area reduction, while portions of the trailing edge of the same billet are still being reformed and reduced in area in the first stage. Due to the fact that the cross sectional area in the second stage is reduced to a smaller figure than the reduction in the first stage, and considering that the volume of billet metal remains constant, it will be apparent that the rate of feed in the second stage is considerably less than the rate of output feed of the first stage. In view of the fact that the total length of the guiding channel, is of course, fixed, it will be apparent that the varying rate of area reduction and therefore billet elongated presents a considerable problem in repeater mill operation. This has in fact been the experience of those skilled in the art, with the result that mills of the type here under consideration have been found to frequently be out of service as a result of jamming and billet tangling in the various stages.

Accordingly, it is a primary object of the invention to provide a repeater mill having unique features designed to accomplish the smooth and continuous flow of the billet therein.

It is a further object of the invention to provide a repeater mill having means associated therewith to accommodate billet elongation during the simultaneous operation of successive stages ona single billet.

It is a specific object of the invention to provide an arrangement of the type described, wherein the guiding channel has associated therewith a selectively operated flipper arrangement adjacent the output side of one stage to selectively engage a portion of the feeding billet and so deform same as to accommodate the simultaneous variation in cross sectional area reduction and elongation rates mentioned above.

These and other objects of the invention will become apparent in the course of the following description, and from an examination of the associated drawings, wherein:

FIGURE 1 is a plan view of a typical feeding channel associated with a repeater mill of the type under consideration,

FIGURE 2 is a front elevational view of the structure shown in FIGURE 1, and

FIGURE 3 is a sectional view taken along line 3-3 of FIGURE 1.

Describing the invention in detail, it will first be noted that the structure illustrated in the drawings shows only a single stage in a repeater mill illustrating two passes on a billet. As noted above, a number of passes desired in any given operation depends on the material being produced, and therefore may vary from operation to operation.

For illustrative purposes, a first pass is indicated in phantom at 2. A second pass is indicated in phantom at 4-. For purposes of the present invention, it is not necessary to show in detail the operative structure of the passes 2 and 4 in that, as is well known to those skilled in the art, each pass comprises appropriate dies and power means to act upon the feeding billet, reform same and reduce the cross sectional area thereof. Therefore, it will be understood that as the billet moves through pass 2, it will be acted upon so as to reform, reduce in cross section and elongate the billet. After passage through pass 2, the billet enters the guiding channel indicated generally at 6. The guiding channel 6 comprises a base or floor plate 8 which is preferably arcuately formed as seen in plan view. The channel 6 further comprises a first upstanding plate 10 secured to the base plate 8 and, as seen in plan view, formed to the desired contour. The upstanding plate or wall 10 defines the inner limit of the channel 6, and is preferably substantially perpendicular to the base plate 8. The channel 6 is further defined by a second wall or plate 12 spaced radially outwardly from the inner wall or plate 10, and also secured at its lower end to the base plate 8. In order to facilitate the action hereinafter described, it is desirable to slope or form the leading edge of the outer wall 12 outwardly, as at 14, into an acute angular relationship with the vertical. This structure is illustrated clearly in FlGURE 2. As the outer wall 12 progressively defines the outer segment of the channel 6 and enters the base of the U-shaped section, it is desirable to gradually reverse the acute angular relationship of said wall with the vertical and bend same inwardly toward the center of the channel. This structure is progressively illustrated at 16. This inward acute angular relationship of the outer wall 12 continues to the termination of the channel 6 at 18, which is spaced somewhat from the second stage 4. To aid entry of the leading edge of the billet to the second stage 4, a second channel indicated generally at 20, is provided. The second channel 2% is de fined on its inner periphery by the wall 16, and at its outer periphery by the straight plate 22. A cover plate 24 interconnects the upper edge of the plate 22 and the outer surface of the inner wall 6, which together with the base plate 3 defines a funnel-like member to guide the leading edge of the billet into the second stage 4. A plurality of mounting bosses 26, 26 may be secured to the underside of the base plate 8 to provide for proper mounting of the guiding channel in relation to the various stages.

Attention is now directed to FIGURE 3, which is a sectional view taken along line 33 of FIGURE 1. Initially it will be noted that the bottom plate 8 is clearly illustrated. A movable plate 30, commonly known as a flipper, has one end thereof pivoted to the base plate 8, as at 32. The pivot 32 accommodates upward movement of the plate St to a position illustrated in phantom at 34. An air cylinder 36 is mounted immediatelyv below the flipper 30, and comprises a piston rod 38 extending upwardly therefrom for pivotal connection, as at 40, to the lower side of the flipper 30. It will thus be understood by those skilled in the art that upon energizing of the air cylinder 36, the piston rod 38 is moved upwardly through a determined stroke, rapidly raising the flipper plate 30 to the position indicated at 34.

Attention is again directed to FIGURE 1, wherein an electric eye or photoelectric cell is diagrammatically indicated at 41 and mounted in relation to channel 6 and immediately adjacent the second stage 4. For purposes of this disclosure, the photoelectric cell 41 will be referred to as switch means to initiate the action hereinafter described. It will be understood, however, that any other conventional actuating means may be employed to initiate said action-such other means being merely the functional equivalent of the photoelectric cell here employed.

The cell 41 is operatively connected to a conventional solenoid arrangement (not shown), and using conventioal circuitry (not shown), said solenoid arrangement being operatively associated with an air line (not shown) which controllably feeds air to the air cylinder 35. It will thus be understood that upon activation of the photoelectric cell 41, the air cylinder 36 will be actuated, rapidly forcing the flipper 30 upwardly to the position indicated at 34.

In the operation of the mill arrangement illustrated, it will be understood that a billet having been heated to a glowing semi-plastic condition will enter stage 2, whereat it is operated on to reduce the cross sectional area, reform the cross sectional contour, and elongate the billet. As the billet leaves stage 2, it enters the channel 6 and is arcuately guided through the channel and into the funnel 20 immediately prior to stage 4. As the glowing billet passes under the photoelectric cell 41, the cell responds to the light given off thereby and, after a slight time delay to accommodate entry of the leading edge of the billet into the guides of stage 4, the cell actuates cylinder 35 which in turn urges the flipper 30 violently upwardly, which strikes a trailing portion of the feeding billet from stage 2 at that point in the channel 6 adjacent 14. The effect of the blow delivered by the flipper 30 is to deform a portion of the feeding billet upwardly into flip, said trailing portion of the feeding billet out of the channel 6. Recalling that the stage 4 also operates on the billet to reduce the cross sectional area thereof and reform same, as well as causing billet elongation, it will be apparent that the variation in volume feed between the stages 2 and 4 would normally cause the feeding billet to tangle up within the channel 6. However, in the arrangement shown, at the approximate precise moment that the feed variation begins, the flipper 39 is actuated as indicated, and the plastic billet deformed upwardly and out of the channel 6 to allow that portion of the billet between stages 2 and 4 to vary in length in air and away from the confining action of the channel 6. Of course, as the trailing edge of the billet leaves the output side of stage 2, the billet may again be drawn within the confines of channel 6 under the continued feeding action of stage 4. It will also be understood that the inwardly acute angular relationship of the arced portion 16 of the outer wall 12 aids in maintaining the leading edge of the billet within the channel 6 as it is fed therethrough. Also, the outward acute angular relationship of the portion 14 of the outer wall 12 accommodates the flipping or upward deforming action on the billet in response to the movement of the flipper 39.

It will thus be seen that the invention provides a unique and novel arrangement to accommodate continuous and smooth billet flow in a mill of the repeater type. The practical advantages relating to the disclosed arrangement are, of course, increased production per unit of time, as well as the factory area economy incident to the employing of this type of mill.

The invention as shown is by way of illustration and not limitation, and may be subject to modification without departing from the spirit thereof or the scope of the appended claims.

What is claimed is:

1. In a billet-forming repeater mill. the combination of first and second pairs of billet-forming dies in operative series relationship to each other, a billet-guiding channel means including a web and interconnecting the output side of said first pair of dies and the feed side of said second pair of dies, said dies including means to feed the billet therethrough, means mounted in the web of said channel means adjacent the output side of said first pair of dies and movable between an inoperative position in the web of said channel means and an operative position inclined relative to and in the same general direction as that of the movement of the billet, said movable means when in said operative position extending across substantially the entire width of said web to engage a portion of the feeding billet trailing the leading end thereof and to urge said portion upwardly out of said channel means, and switch means associated with the channel means for actuating and moving said movable means in response to a predetermined location of the leading edge of the feeding billet in said channel means.

2. A billet-forming repeater mill comprising a first and second pair of billet-forming dies cooperatively related to each other, a billet-forming guiding channel means extending between the exit of said first and second pairs of billet-forming dies, said channel means being generally curved as viewed in plan and including a pair of spaced apart curved walls interconnected by a web, a flipper means pivotally mounted in the web of the channel means adjacent to the exit side of said first pair of billetforming dies, said flipper means extending along the web of said channel means and-being pivoted about an axis extending laterally of said web to permit the free end of said flipper means to move upwardly relative to said web,

said flipper means extending across substantially the entire width of said web, motor means connected to said flipper means for moving said flipper means upwardly out of said channel means, and switch means located at the end of said channel remote from said flipper means for actuating said motor means when the leading edge of a feeding billet is in the remote end of said channel means, said flipper means being operable to engage a portion of the feeding billet to lift said portion upwardly out of said channel means and permit said feeding billet to expand between said first and second pairs of billetforming dies.

References Cited in the file of this patent UNITED STATES PATENTS 

